mk3 golf idle/running issue

Bondbill2k2 · 08-12-2008, 12:02 PM

Ive read threads on a few forums along with faq's related to this problem and still no luck.

My 1.4 Golf is having problems, when started up from cold it wouldnt tick over but just cut out, after keeping the throttle on for a short period of time till it warmed up the engine would tick over by itself and not cut out but would continusly hunt around 800-1000rpm without settling.

After reading this-
idle issues / cutting out or does your Mk3 run poor? Read this guide for answers

We replaced the ecu temp sensor thinking that may solve it, now thats replaced the engine seems to tick over without cutting out (but stil hunting those revs) until warm, once warm the engine will again just die on us, the revs totaly drop with no attempt to idle (unless foot is on the accelrator around 1000rpm)

Any idea what it could be? cry Most the problems on that link sound unlikly as the problem isnt always

bac2ba6 · 08-12-2008, 04:54 PM

Have a golf mk3 gti and have had similar problems to what your describing and although it wouldn't actually stall when cold the revs would drop to about 450-500 rpm for a brief second causeing to battery lights to flicker on but then would just catch itself again and when warm the revs would flicker between about 850 and 1000 rpm .
All i did was to remove the air filer and hoses and expose the throttle body and removed the top and gave the inside of the throttle body a really good clean with carb cleaner and a small amount of redex straight down it with the revs at about 3000 rpm ! ( there was loads of crap in there ) and from what i have read its a common thing on the mk3's
Anyhow has stopped it almost cutting out and now the revs are much more stable with them being more or less a constant 850rpm ! the idle speed is still very very slightly erratic but its 95% better than it was ! could just be as daft as a build up of crap in the throttle body

rapidresto · 08-12-2008, 08:25 PM

Is it carb or injection? If injection check the throttle body as above, if carb then it could be the box of tricks on the side of the carb that controls the idle. Just had this issue (similar sounding symptoms) on my dads audi 80.

The idle control unit has a little motor and a set of cogs that vary the throttle stop position, and the cogs had stripped. swapped it over with one from the scrappy and all was well again.

rapidresto · 08-12-2008, 08:27 PM

check also the wiring to the inlet manifold heater and the various sensors etc aswell as the earth straps to the engine (infact check this first) .

Bondbill2k2 · 09-12-2008, 01:57 PM

carb cleaner sorted it, just idles at 2000 rpm now!

been told normly this is caused by a faulty ecu temp sensor (we replaced this yesterday)

rapidresto · 09-12-2008, 03:09 PM

If you've replaced the temp sender, either take the car for a good long drive or try disconnecting the battery for a while to reset the ecu (remember to note the radio code if original radio).

check all the breather pipes for leaks / blockages.

Bondbill2k2 · 09-12-2008, 11:09 PM

Takeing it to vw rescue in wombourne let them sort it out. Anyone used them before? Heared good things about them?

Bondbill2k2 · 10-12-2008, 09:52 PM

quick diagnostics and a reset sorted